JP3373404B2 - Flame-retardant polyester resin composition for lighting parts with good light discoloration resistance - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant polyester resin composition for lighting parts, which has good resistance to light discoloration.

[0002]

2. Description of the Related Art Conventionally, polyester resins have been widely used for lighting parts, but recently the downsizing of fixtures and the increase in brightness of light sources have led to prevention of discoloration when exposed to strong light or high temperature. It has become a challenge. Further, from the viewpoint of ensuring the safety of products, it is required to impart flame retardancy. However, when the flame-retardant composition containing the brominated flame retardant is exposed to ultraviolet rays, there is a problem in that the product yellows to reduce the commercial value. Further, when a flame retardant or a light stabilizer is added, it may be colored yellow, and it may be difficult to adjust to white while maintaining various properties, and further improvement has been desired.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a novel flame-retardant polyester resin composition for lighting parts, which has good resistance to light discoloration. is there. The object of the present invention is to achieve the above object by making the initial yellow coloring of the composition by the two-center energy between carbon and bromine and the brominated flame retardant, and optionally the brominated flame retardant and the light stabilizer within a specific range. Another object is to provide a flame-retardant polyester resin composition for lighting parts, which has good resistance to light discoloration. Further objects and advantages of the present invention will be apparent from the following description.

[0004]

Means for Solving the Problems As a result of earnest studies to develop a flame-retardant polyester resin composition having excellent resistance to light discoloration, the present inventors have found that carbon and bromine constituting the flame-retardant molecule are present. A flame-retardant polyester resin composition having a central energy of 2 and a brominated flame retardant, and optionally a brominated flame retardant and a light stabilizer in an initial yellow coloring range within a specific range exhibits good moldability. At the same time, they have found that yellowing when exposed to ultraviolet rays is extremely small, and that they can be toned in various colors, thereby increasing the commercial value of the product when used as a lighting component, and reached the present invention.

According to the present invention, the above objects and advantages are based on 100 parts by weight of the thermoplastic aromatic polyester, (A) 0 to 150 parts by weight of the inorganic filler, and (B) 5 to 60 parts by weight of the brominated flame retardant. A flame-retardant polyester resin composition comprising 0 to 20 parts by weight of (C) an antimony-based flame retardant aid and 0 to 5 parts by weight of (D) a light stabilizer, which is a bromine-based flame retardant (B). Satisfies that the two-center energy between carbon and bromine calculated using the molecular orbital method is -12.25 eV or less for the molecular model of the brominated flame retardant or the low molecular model of the brominated flame retardant. And a flame-retardant polyester resin composition having a b * value of 10 or less in initial yellow coloring, which is excellent in light discoloration resistance, and is achieved by a flame-retardant polyester resin composition for lighting parts.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below. The thermoplastic aromatic polyester used in the present invention is
An aromatic polyester whose acid component is terephthalic acid or naphthalene dicarboxylic acid and whose diol component is at least one kind of aliphatic diol such as ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, neopentyl glycol, etc. The main component. The main component is preferably 80 mol%, more preferably 90 mol%, particularly preferably 95 mol% or more of the total amount of the thermoplastic aromatic polyester. Of these, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate and polybutylene naphthalate are preferred.

Further, the thermoplastic aromatic polyester may be a polyester obtained by substituting a part of the above polyester with a copolymerization component. Examples of the copolymerization component include isophthalic acid,
Phthalic acid; Alkyl-substituted phthalic acid such as methyl terephthalic acid and methyl isophthalic acid; 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid and other naphthalene dicarboxylic acids; 4,4 ' -Diphenyldicarboxylic acids such as diphenyldicarboxylic acid and 3,4'-diphenyldicarboxylic acid; aromatic dicarboxylic acids such as diphenoxyethanedicarboxylic acid such as 4,4'-diphenoxyethanedicarboxylic acid, succinic acid, adipic acid, sebacine Acid, azelaic acid, decanedicarboxylic acid,
Aliphatic or alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, alicyclic diols such as 1,4-cyclohexanedimethanol, dihydroxybenzenes such as hydroquinone and resorcin; 2,2'-bis (4-hydroxyphenyl) propane , Bisphenols such as 2,2'-bis (4-hydroxyphenyl) sulfone; aromatic diols such as ether diols obtained from bisphenols and glycols such as ethylene glycol, ε-oxycaproic acid, hydroxybenzoic acid, hydroxy Examples thereof include oxycarboxylic acids such as ethoxybenzoic acid. When these copolymerization components are copolymerized, the copolymerization ratio is preferably 20 mol% of the total acid components, more preferably 10 mol%.
It is the following.

Further, as a branching component in the above aromatic polyester, an acid having a polyfunctional ester forming ability such as trimesic acid and trimellitic acid, or a polyfunctional ester forming ability such as glycerin, trimethylolpropane and pentaerythritol is provided. The alcohol contained may be copolymerized at a ratio of 1.0 mol% or less, preferably 0.5 mol% or less, more preferably 0.3 mol% or less.

The thermoplastic aromatic polyester used in the present invention preferably has an intrinsic viscosity of 0.4 to 1.2. 0.4
If it is smaller than 1.2, sufficient properties cannot be obtained, and if it is larger than 1.2, the melt viscosity is high and the fluidity is lowered to deteriorate the moldability, which is not preferable. Here, the intrinsic viscosity number (the same as the intrinsic viscosity) is measured at 35 ° C. using o-chlorophenol as a solvent.

The inorganic filler (A) used in the present invention is a granular or amorphous filler such as calcium carbonate, titanium oxide, feldspar minerals, clay, white carbon, carbon black, glass beads, etc .; Kaolin clay , Plate-like fillers such as talc; scaly fillers such as glass flakes, mica, graphite; fibrous fillers such as glass fibers, carbon fibers, wollastonite, potassium titanate, etc. .

The amount of the inorganic filler (A) used in the present invention is 0 to 150 parts by weight, preferably 0 to 120 parts by weight, more preferably 0 to 100 parts by weight, based on 100 parts by weight of the thermoplastic aromatic polyester. Is.

The light discoloration resistance in the present invention is light discoloration resistance in which substantially no yellowing is observed during the life of a product as an illumination component. More specifically, this light discoloration resistance is 250 hours at a distance of 20 cm from two fluorescent lamps of 96 W at 80 ° C.
In the accelerated deterioration test of irradiation, ΔE ^* is 5 or less when judged by measuring ΔE ^* , which is light discoloration resistance. The resin composition of the present invention having this light discoloration resistance does not substantially yellow in the product life as a lighting part, and enhances the commercial value of the product when used as a lighting part.

Brominated flame retardant used in the present invention
(B) means that the two-center energy between carbon and bromine of the bromine-based flame retardant (B), calculated using the molecular orbital method, is -12.
It is a brominated flame retardant that satisfies 25eV or less. If the two-center energy between carbon and bromine is greater than -12.25eV, the yellowing will be large when exposed to ultraviolet rays.

The method used in the present invention as the molecular orbital method is the MOPAC93 AM1 method, and ENPART was used as a calculation option.

MOPAC93 is a semi-empirical molecular orbital calculation package software developed by JJP Stewart.
M1 method is NDDO (Neglect of Diatomic Differential Over
It is a semi-empirical molecular orbital method based on the (lap) approximation and gives almost reasonable calculation results for general organic compounds.

The option Enpart is a method of allocating the energy of a molecule calculated by semi-empirical calculation to each atom (1 central energy) and between atoms (2 central energy) by the Malliken Energy-Partition method. The two-center energy calculated by this method is an amount corresponding to the energy of the bond and serves as a measure of the easiness of breaking the bond.

In the molecular orbital method, if the Hamiltonian and the basis function are the same, it is possible to obtain the same value as the physical property of an arbitrary molecule even if other methods and programs are different. In semi-empirical method, the basis function is Minimal
Therefore, if a program using AM1 as the Hamiltonian is evaluated by the Energy-Partition method, the same calculation result can be obtained. For example, Gaussian
94, Hyper Chem, etc. support AM1 method.

On the other hand, when the molecular orbital method in which the Hamiltonian and the basis function are different is calculated, the result does not always become exactly the same, but in the method in which the Hamiltonian in the same series is used, the calculation results have similar tendencies. . For example, the MNDO method and the PM3 method have similar tendency calculation results.

Regarding the molecular orbital method, the molecular orbital method MOP is used.
AC Guidebook, Tsuneo Hirano, Kazutoshi Tanabe, Kaibundou Publishing, (1991), Molecular Orbital Method, Shigeru Fujinaga, Iwanami Shoten, (1980).

The brominated flame retardant molecular model is a molecular model of the flame retardant molecule. The molecular model represents a molecule to be calculated as a chemical structural formula, and the molecular model is composed of data such as atomic coordinates and electron density of atoms and electrons constituting the molecule.

The low molecular weight model of the brominated flame retardant is
It is a molecular model of a compound formed by blocking the ends of divalent residues corresponding to repeating units with a hydrogen atom or a phenyl group in a polymeric flame retardant. A hydrogen atom or a phenyl group is selected so as to have a resonance structure close to that of the original polymer for the end blocking.

The two-center energy is energy corresponding to the binding energy of the bromine atom bonded to the benzene ring. The larger the negative value, the more stable the bromine atom becomes when it is exposed to ultraviolet rays, and the more stable the light resistance is. The property becomes good.

When the two central energies obtained differ depending on the substitution position of the bromine atom, the most unstable value is represented.

On the other hand, when the composition containing the brominated flame retardant (B) has a large yellow coloration, a large amount of the colorant must be used for toning, and other properties are largely deteriorated. Absent. The initial yellow coloration of the composition by blending the brominated flame retardant (B) used in the present invention is 10 or less, preferably 7.5 or less as a b * value.

Examples of brominated flame retardants satisfying the above conditions include brominated bisphenol A compounds. Suitable brominated bisphenol A-based compounds include brominated bisphenol A-based polycarbonates represented by the following general formula (I) and brominated bisphenol A-based epoxy resins represented by the following general formula (II). it can.

[0026]

[Chemical 1]

[0027]

[Chemical 2]

The terminal structure of the brominated bisphenol A-based polycarbonate (I) is not particularly limited, but 4-t-butylphenyl group, 2,4,6-tribromophenyl group and the like can be exemplified.

The molecular weight of the brominated bisphenol A type polycarbonate (I) is preferably 1000 to 18000.
The softening point of brominated bisphenol A-based polycarbonates (I) varies depending on the molecular weight and the molecular weight distribution.
It is preferably in the range of up to 300 ° C.

Brominated bisphenol A type epoxy resins
The molecular weight of (II) is preferably 650 to 45,000. The softening point of the brominated bisphenol A-based epoxy resins (II) varies depending on the molecular weight and the molecular weight distribution, but is preferably in the range of 100 to 250 ° C.

Among these flame retardants, brominated bisphenol A-based polycarbonates and brominated bisphenol A-based epoxy resins having good discoloration resistance are particularly preferable. These flame retardants can be used in combination.

The amount of the brominated flame retardant (B) used in the present invention is 10% by weight of the thermoplastic aromatic polyester resin.
It is 5 to 60 parts by weight, preferably 10 to 50 parts by weight, per 0 parts by weight. The larger the amount of the inorganic filler in the total composition, and the smaller the amount of the flame retardant when the flame retardant auxiliary is used in combination, even in that case, at least in order to achieve the object of the present invention. 5 parts by weight is necessary, and if it is less than 5 parts by weight, the flame retardancy of the resulting composition is insufficient.

When the antimony-based flame retardant aid is used in the present invention, the antimony-based flame retardant aid (C) functions to enhance the flame retardancy by a synergistic effect with the brominated flame retardant (B). Is.

Examples of suitable flame retardant aids include Sb2O3 and / or
Alternatively, x Na2O.Sb2O5.yH2O (x = 0 to 1, y = 0 to 4) can be mentioned. The particle size of the flame retardant aid is not particularly limited, but is 0.
02-5μ is preferable. If desired, those surface-treated with an epoxy compound, a silane compound, an isocyanate compound, a titanate compound or the like can be used.

The amount of the antimony-based flame retardant aid (C) used in the present invention is 0 to 20 parts by weight, preferably 1 to 15 parts by weight. In order to effectively impart flame retardancy, it is preferable to add 20 to 70% by weight of the flame retardant. If the blending amount exceeds 20 parts by weight, the decomposition of the resin or the compounding agent is promoted and the characteristics of the molded product may be deteriorated, which is not preferable.

The composition of the present invention has an initial yellow coloration of b * value of 10 or less, preferably 7.5 or less. Light stabilizers may be used to achieve this b * value. Examples of such light stabilizers include triazole compounds, benzoate compounds and hindered amine compounds.

Light stabilizer (D) used in the present invention
The compounding amount is 0 to 5 parts by weight, preferably 0.001 to 1 part by weight. If the blending amount exceeds 5 parts by weight, the product may be colored yellow, which is not preferable.

As described above, the type and blending amount of the light stabilizer are appropriately adjusted so that the initial yellow coloration of the composition is 10 or less, preferably 7.5 or less as the b * value.

The resin composition of the present invention contains additives such as a nucleating agent, a lubricant, an antioxidant, an ultraviolet absorber, a heat stabilizer, an antistatic agent and a pigment, as long as the object of the present invention is not impaired. Further, modifiers such as impact modifiers and fluidity modifiers may be contained.

The method for producing the resin composition of the present invention is not particularly limited, and known methods can be adopted.
That is, after the thermoplastic aromatic polyester, the inorganic filler (A), the bromine flame retardant (B), the antimony flame retardant aid (C) and the light stabilizer (D) are uniformly mixed using a blender or the like, Using a Banbury mixer, heating roll, single-screw or multi-screw extruder, etc., 230 to 360 ° C, preferably 23
It can be produced by various methods such as a method of melting and kneading at a temperature of 0 to 290 ° C. It is also possible to preliminarily knead a part of the components of the resin composition and then adjust the mixture ratio to a predetermined value and then knead the mixture.

[0041]

EXAMPLES The present invention will be described in more detail below with reference to examples. In addition, the part in an Example means a weight part. The characteristics of the molded product were measured by the following methods.

1. Initial yellow coloring of the composition: A disc-shaped test piece is formed, and the b * value is measured and judged.

2. Resistance to light discoloration: At 80 ° C, a disc-shaped test piece was irradiated with two 96W fluorescent lamps for 250 hours from a distance of 20 cm for an accelerated deterioration test, and ΔE ^* was measured to determine.

3. Flammability: In accordance with the method of Subject 94 (UL-94) of Underwriter Laboratories in the United States, it is evaluated using a test piece of a predetermined thickness. The compounding agents used in the examples will be described below. Thermoplastic aromatic polyester: PBT Teijin Ltd. IV: 0.875 PET Teijin Ltd. IV: 0.71 A. Inorganic filler: Titanium oxide CR-80 glass fiber manufactured by Ishihara Sangyo Co., Ltd. ECS-03-T124 manufactured by Nippon Electric Glass Co., Ltd. B. Bromine-based flame retardant: Br-PC FG7100, FG8500 Br-Ep made by Teijin Chemicals Ltd. EP100 made by Dainippon Ink and Chemicals, Inc. PDBS-80 made by Great Lakes Chemical Corporation BT93W made by Albemarle Brominated benzyl acrylate Dead Sea Bromine FR1025 C.I. Antimony flame retardant aid Sb2O3 PATOX-M Sodium Antimonate Co., Ltd. NA1030 manufactured by Nissan Chemical Industries, Ltd. D. Light Stabilizer: Triazol type Asahi Denka Co., Ltd. LA-31 Benzoate type Sumitomo Chemical Co., Ltd. Sumysorb 400 Hindered amine type Asahi Denka Co., Ltd. LA-57

[Examples 1 to 4 and Comparative Examples 1 to 3] The blending components shown in Table 1 were preliminarily uniformly dry blended at a predetermined ratio, and then a cylinder was prepared using a vented twin-screw extruder having a screw diameter of 44 mm. The mixture was melt-kneaded at a temperature of 250 ° C. to 260 ° C., a screw rotation speed of 160 rpm, and a discharge rate of 40 kg / h, extruded into a thread shape, cooled and cut to obtain a molding pellet. Then, using this pellet, injection volume 1
Cylinder temperature: 250 on a 45 cm ³ injection molding machine
° C, mold temperature: 60 ° C, injection pressure: 800 kg / c
A disc-shaped test piece was molded under the conditions of m ² , cooling time: 15 seconds, and total molding cycle: 26 seconds. 80 ℃ for this test piece
, Two 96W fluorescent lights from a distance of 20 cm for 250 hours
An accelerated deterioration test of irradiation was conducted, and ΔE ^* was measured to evaluate the light discoloration resistance. In addition, the molecular orbital method (MOPAC93A
M1, calculation option: ENPART) was used to calculate the two central energies between carbon and bromine. The results are shown in Table 1.

[0046]

[Table 1]

The composition of the present invention exhibited flame retardancy, and because the initial yellow coloring was small, it was easy to adjust the color and the light discoloration resistance was also good.

[Examples 5 to 7] The compounding components shown in Table 2 were melt-kneaded in a predetermined ratio in the same manner as in Example 1 and extruded to obtain molding pellets, which were molded into disc-shaped test pieces. The light discoloration resistance was evaluated. The results are shown in Table 2.

[0049]

[Table 2]

All of them showed good flame retardancy, and the light resistance stability was improved by the combined use of a light stabilizer.

[Examples 8 and 9] The compounding components shown in Table 3 were melt-kneaded at a predetermined ratio in the same manner as in Example 1 and extruded to obtain molding pellets, which were molded into disc-shaped test pieces. The light discoloration resistance was evaluated. The results are shown in Table 3.

[0052]

[Table 3]

All of them showed good flame retardancy, and since the initial yellow coloring was small, it was easy to adjust the hue with a coloring agent.

Claims (4)

(57) [Claims] 1. An inorganic filler of 0 to 150 parts by weight, (B) a brominated flame retardant of 5 to 60 parts by weight, and (C) an antimony flame retardant auxiliary to 100 parts by weight of a thermoplastic aromatic polyester. 0 ~ 20
A flame-retardant polyester resin composition containing 0 to 5 parts by weight of (D) a light stabilizer, wherein the brominated flame retardant (B) is a molecular model of the brominated flame retardant or the bromine. The low-molecular model of the flame retardant was satisfied that the 2-center energy between carbon and bromine calculated using the molecular orbital method was -12.25 eV or less, and the flame-retardant polyester resin composition had an initial yellow color. A flame-retardant polyester resin composition for lighting parts, which has a b * value of 10 or less for coloring and has good light discoloration resistance. 2. The thermoplastic aromatic polyester is polyethylene terephthalate, polybutylene terephthalate,
The flame-retardant polyester resin composition for lighting parts according to claim 1, which is and / or a mixture thereof. 3. The flame-retardant polyester resin for lighting parts according to claim 1, wherein the brominated flame retardant (B) is a brominated bisphenol A-based polycarbonate and / or a brominated bisphenol A-based epoxy resin. Composition. 4. A lighting component comprising the flame-retardant polyester resin composition according to any one of claims 1 to 3.